Nine subjects (experimental group) were tested on rapid elbow flexion and extension movements performed in the same final position, before and after extensive practice of the movements. Nine additional subjects (control group) were also tested, but without any practice between the tests. Comparison of the pretest and posttest results suggested that the experimental group decreased their variable error (i.e., standard deviation of the final movement position) in both practiced (elbow flexion) and nonpracticed (elbow extension) movements. The control group, however, did not improve in either of tested movements. The experimental group demonstrated lower variable error in the nonpracticed elbow extensions than the control group, while the same difference for practiced elbow flexion movements was slightly below the level of significance. The results support the importance of the final position in programming of rapid, self-terminated movements; however, they do not rule out the role of other kinetic and kinematic variables (such as movement distance).
Dusko B. Ilic and Slobodan Jaric are with The Research Center, Faculty for Physical Culture, University of Belgrade, Yugoslavia. Dragan M. Mirkov is with the School of Medicine, University of Belgrade. Slobodan Jaric is also with the Institute for Medical Research, Belgrade. Direct correspondence to Slobodan Jaric, The Research Center, Faculty for Physical Culture, B. Parovica 156, 11030 Belgrade, Yugoslavia.